Hydrocarbons, C18-C22, n-alkanes, n-alkenes

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across source

Preliminary study:

A preliminary study was not conducted.

Test performance:

Amount of SSO and the calculated theoretical CO2 (ThCO2)
SSO
Replicate 1: 21.0 mg product = 64.87 mg ThCO2
Replicate 2: 19.2 mg product = 59.31 mg ThCO2
Replicate 3: 19.3 mg product = 59.62 mg THCO2
Replicate 4: 19.4 mg product = 59.93 mg THCO2

Key result

Parameter:

% degradation (O2 consumption)

Value:

76.3

Sampling time:

28 d

Details on results:

The test substance exhibited rapid biodegradation and assessed as readily biodegradable. By Day 28, the average percent biodegradation of the test substance was 76.3%. The test substance reached 10% biodegradation on approximately Day 1.4 and 60% biodegradation on Day 11.
Biodegradation was based on oxygen consumption and the theoretical oxygen demand of the test substance was calculated using results of an elemental analysis of the test substance.

Results with reference substance:

The reference compund reached 60% ThCO2 by day 3.

Ultimate biodegradation:

Day	Biodegradation [%]
1	3.6
2	12.7
3	23.3
4	33.6
5	41.0
6	45.4
7	49.2
8	51.7
9	53.7
10	55.5
11	57.2
12	59.1
13	61.7
14	63.2
15	64.3
16	65.9
17	65.9
18	67.3
19	69.3
20	69.7
21	70.8
22	71.6
23	71.8
24	73.8
25	74.4
26	75.3
27	75.6
28	76.3

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Hydrocarbons, C16 -C23, n-alkanes, alkenes biodegraded 76.3% after 28 days under the conditions of the study and is readily biodegradable.

Executive summary:

Hydrocarbons, C16 -C23, n-alkanes, alkenes biodegraded to an extent of 76.3% after 28 days. The data support characterizing the test substance as rapidly biodegradable, readily biodegradable, not expected to persist in the environment under aerobic conditions. It met the 10 -day window requirement and is characterized as readily biodegradable.

Description of key information

The study was conducted according to a standard guideline (OECD 301F) and was conducted with minor deviations, but was not conducted under a GLP guideline.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

Hydrocarbons, C16 -C23, n-alkanes, alkenes biodegraded to an extent of 76.3% after 28 days. The data support characterizing the test substance as rapidly biodegradable, readily biodegradable, not expected to persist in the environment under aerobic conditions. It met the 10 -day window requirement and is characterized as readily biodegradable.